5. Don't let HID the bandwagon jumpers deter you.
I run a setup with 2-CFL hoods, ONLY. One is 334 watts, the other is 300. The total lumens for hood #1 is 22,000+. The hood is roughly 1-2" away from the plant's foliage and/or buds. So considering light diminishes at the square of the distance (measured in FEET), at an inch or two there is a negligible loss in lumens, with all other factors mentioned in this post being in place.
Most people go with a 600 or 1000-watt HPS for flowering, and scream "CFLs can't make dense buds..blah, blah." Now, remember, a 1,000 watt will need to be kept at least 2 feet away from the top of the plant/foliage, usually more. A 600 watt will need to be kept 18 inches to two feet or more away from plants, due to the intense amount of heat being generated, unless a cooltube is being used. And we all know a cooltube reduces the lumen output even further.
==> A 1000 watt HPS has 140,000 lumens at 1 foot away;
35,000 lumens at two feet away.....
==> A 600 watt HPS has 90,000 lumens one foot away;
22,500 lumens at two feet away.....
==> My 334 watt CFL hood has roughly
20,000 lumens at 1-2 inches away...
(
Lumens + wattage) + proper placement = HUGE light intensity = Excellent buds!